The Unfinished Science Behind the New Wave of Electrical Brain Stimulation | WIRED

Ever since the physician Scribonius Largus slapped an electric torpedo fish on the forehead of a headache sufferer in the early days of the Roman empire, electricity has been pursued as a cure for a seemingly endless variety of ailments–by serious scientists and profiteering quacks alike. The latest chapter in this long and colorful history involves something called transcranial direct current stimulation, in which a small electric current is delivered to the brain through electrodes placed on the head.